Microfluidic devices include “Lab on a chip” devices. “Lab-on-a-chip” (LOC) devices is a term in use for devices that integrate (multiple) laboratory functions on a single chip of only square millimeters to a few square centimeters in size and that are capable of handling extremely small fluid volumes down to less than pico liters. Lab-on-a-chip devices are a subset of MEMS devices and often indicated by “Micro Total Analysis Systems” (μTAS) as well. Microfluidics is a broader term that describes also mechanical flow control devices like pumps and valves or sensors like flowmeters and viscometers. However, strictly regarded “Lab-on-a-Chip” indicates generally the scaling of single or multiple lab processes down to chip-format, whereas “μTAS” is dedicated to the integration of the total sequence of lab processes to perform chemical analysis. The term “Lab-on-a-Chip” was introduced later on when it turned out that μTAS technologies were more widely applicable than only for analysis purposes.
One specific problem concerns the manufacture of conduits and/or processing or reaction chambers within the “chips”, which hereinafter will be indicated as (processing) modules as well. Prior art processing modules may be made of a thermoplastic or a thermosetting synthetic resin in which conduits and reaction chambers are made from the upper and/or lower side, e.g. by means of moulding or by means of machining, after which the conduits and chambers are closed by means of a cover layer which e.g. is sealed, bonded or laser-welded to the reaction module, thus forming interior conduits and chambers. This method, however may introduce a certain level of contamination in the fluidic conduits and chambers and, moreover, is more expensive. Further, as to the field of the invention, wiring structures supported by a carrier body may be in use in electronic and electromechanical gear, e.g. in vehicles (cars, trucks, airplanes etc.), machinery or other equipment. Such wiring structures often include a carrier or support body, on which or in which a plurality of isolated copper wires are mounted. Where such a wiring structure is formed by one or more synthetic carriers comprising one or more metal conductors, the manufacturing of such structure may be rather complex due to the fact that the metal conductor(s) has (have) to be made in a separate process and inserted into a mould which, subsequently, is filled with a viscous, hardenable synthetic material, which encloses—entirely of partially—the metal conductor. Besides, well-known are printed circuit boards, comprising a two-dimensional carrier, and a wiring structure on one or both sides of the carrier. Most PCBs are composed of between one and twenty-four conductive layers separated and supported by layers of insulating material (substrates) laminated (glued with heat, pressure & sometimes vacuum) together. The vast majority of printed circuit boards are made by adhering a layer of copper over the entire substrate, sometimes on both sides, (creating a “blank PCB”) then removing unwanted copper after applying a temporary mask (e.g. by etching), leaving only the desired copper traces. A few PCBs are made by adding traces to the bare substrate (or a substrate with a very thin layer of copper) usually by a complex process of multiple electroplating steps. Some PCBs have trace layers inside the PCB and are called multi-layer PCBs. These are formed by bonding together separately etched thin boards.